Mandrel



H. F. MARANVILLE.

MANDREL.

APPLICATION FILED own, 1919.

LSQUfiQQ. .Patentedgept- 13, 1921..

HARVEY F. MARANVILLE, 0F AKRON, OHIO, ASSIGNOR TO THE MILLER RUBB 00M-PANY, 0F AKRON, OHIO, A CORPORATION 01E OHIO.

MANDREL.

Specification of Letters Patent. ll gmignt-gdl te t, 13 1921 Applicationfiled December 11, 1919. aerial No. 344,130.

To all whom it may concern.

Be it known that l, HARVEY F. MARAN- VILLE, a citizen of the UnitedStates, residing at Akron, in the county of Summit and State of Ohio,have invented a certain new and useful Improvement in Mandrels, of whichthe following is a full, clear, and exact description, reference beinghad to the accompanying drawings. v This invention relates to mandrelsfor use in making pneumatic tires and certain parts and adjuncts thereofsuch as inner tubes and air bags. These tubular rubber members are firstmolded, and sometimes cured also, upon a circular metal ring and thenremoved and their ends suitably joined together. The objects of thepresent invention are the provision of a mandrel for this purpose of newand improved construction and having peculiar provisions forfacilitating the removal of the formed article; the provision of amandrel of uniform and complete circular shape, adapted for machineoperation, and capable of being separated in a new and better way toenable the removal of the tubular rubber part; the provision of new andimproved means for securing together and operating the parts of a tubemandrel; the provision of new and improved expedients for removing thetube; while further objects and advantages of the invention wili becomeapparent as the description proceeds.

In the drawings accompanying and forming a part of the specification Ihave illustrated certain embodiments of my said invention, although itwill be understood that my inventive idea is capable of use in a largenumber of different physical constructions wherefore I do not limitmyself to the details of construction and arrangements shown hereinexcept as the same are recited in my claims. In these drawings Figure 1is a side view of a complete mandrel embodying my improvements; Fig. 2is a vertical sectional view of the mandrel illustrated in Fig. 1showing the two parts thereof displaced relatively to each other; Fig. 3is a-detail sideelevation of the swinging ends of the man drel; Fig. 4is a longitudinal sectional view of the opposite ends showing the hinge;and Fig. 5 is a sectional view on the line 5-5 of Fig. 4 looking in thedirection of the arrows; Fig. 6 shows a modified construction of theswinging ends, and Fig. 7 illustrates a complete mandrel embodying thismodification.

Describing the parts by reference characters, my lmproved mandrelconsists of a torus-shaped body made in two parts, 1, 2, ofsubstantially equal angular extent, hinged together at one end anddetachably connect ed at the opposite end. Each segment is hollow andhas its ends closed by plugs 3-3 and transverse webs 4-4 respectively.The plugs -3 are formed with alined circular apertures for the receptionof a securing bolt 5 which is here shown as provided with two removableheads 6-6, secured to the bolt by drift pins 7-7. In the present embodiment T have shown the plugs as rigidly secured in place by radialscrews 8, 8, which maybe reinforced by (or substituted'with) brazing orother securing means. When made in this manner the two plugs are securedtogether upon the bolt prior to their insertion in the mandrel sections.

As a result of this construction the two members of the mandrel can bemoved relatively to each other about this bolt as an axis as shown in.

Fig. 2.

The webs 4-4 are provided with cooperating tongue and groove, shown inFigs. 1, 2, and 3 as of dove-tail shape and indicated at 11 and 12respectively, the same being curved on an arc of which the bolt 5 is thecenter. The wall of each segment is also preferably formed with a numberof air escape apertures 1515 so that by admitting compressed air to theinterior of the mandrel the rubber member thereon can be forced out ofcontact therewith and its removal facilitated. Suitable means areprovided for admitting such compressed air to the mandrel interior suchas forming one of the members adjacent to the swinging end with athreaded aperture 16, here shown as formed in one of the webs 4 but notrestricted to that location. In order to permit such compressed air topass through the other member the bolt 5 is formed with a longitudinalbore 17.

In Figs. 1 and 3 the swinging ends are cut on a plane parallel to theradius at that point, but this is not essential and in Figs. 6 and 7 Ihave shown the ends as inclined. Also I have shownlthe tongue and grooveas flat sided instead of undercut. Also I have shown the parts asprovided with mechanical means for maintaining them in alinement, thesame here consisting of a spring pressed bolt 16 carried in one memberand having a rounded head adapted to engage a suitable socket in theother member. In this view I have-shown the air inlet aperture at 18.

In use the ends of the mandrel are brought to the same plane as shown inFigs. 1 and 3, and the rubber fabric, and other components are appliedthereto in the usual manner either by hand or by machine, and if desiredsome or all of the curing is performed. The tube may either be builtunbroken across the swinging ends or it may be discontinued at thispoint, although in the former case it is necessary to sever the samebefore the mandrel can be opened; and in either case, when it is desiredto remove the tube, the parts are displaced as shown in Figs. 2 and 7and compressed air admitted to the mandrel interior which frees the tubefrom adhesion and permits it to be drawn readily therefrom.

Nhile there are advantages in having the pivot axis coaxial with thesections at the point of attachment my invention is not limited to this;also while there are advantages in having the two segments of equallength, a perfectly operative and highly valuable device can be madewith unequal sections; also many other changes in detail can be madewithin the scope of my inventive idea, especially in the mode of hingingthe hinged ends and in guiding and holding the swinging ends, and I donot restrict myself in any way except as recited in the claims heretoannexed. While it have mentioned both tubes and air bags I have devisedthis construction more especially for use in making air bags as commonlyused in the process of making cord tires.

Having thus described my invention, what I claim is 1. A tube or air bagmandrel for use in pneumatic tire manufacture comprising an annular bodymade in two segments which are pivoted together at one end to swinglaterally.

2. A tube or air bag mandrel for use in pneumatic tire manufacturecomprising an annular body made in two segments which are pivotedtogether at one end and det-aclr ably connected together at the oppositeend.

3. A tube or air bag mandrel for use in pneumatic tire manufacturecomprising an annular body made in two segments which are pivotedtogether at one end upon an axis substantially concentric with thesection of the torusat that point.

4. A. tube or air bag mandrel for use in pneumatic tire manufacturecomprising an annular body made in two substantially equal segmentswhich are pivoted together.

5. A. tube or air bag mandrel comprising an annular body made in twosegments which are pivoted together at one end upon an axissubstantially concentric with the section of the torus at that point andare formed with interfitting tongue and groove provisions at the otherend concentric with such binge.

(3. A tube or air bag mandrel comprising an annular body made in twosubstantially equal segments which are pivoted together at one end andare formed with interfitting dove tailed tongue and groove provisions atthe other end concentric with the hinge axis, and means for holding thelast named ends in alinement.

7. An annular two piece mandrel made of hollow members of substantiallyequal angu lar extent having end closures, two of said closures beingapertured for the reception of a pivot bolt, a bolt in said aperture andhaving at least one removable head, and means including a pin forsecuring said head to the bolt.

8. An annular two piece mandrel made of hollow members having endclosures, two of said closures being adapted for the reception of apivot bolt, a bolt therefor, and the other closures having interlittingparts adapted to cooperate with said bolt to hold said members together.

9. An annular mandrel comprising two hollow body members ofsubstantially equal angular extent, and pivoted together at one end uponan axis within the limits of the body members.

10. An annular mandrel comprising two hollow body members ofsubstantially equal angular extent, and pivoted together at one end uponan axis within the limits of the body members, the walls of said membersbeing formed with air escape perforations, and one of said members beingformed with an air admission aperture, the pivot means comprising an airconduit between one member and the other.

11. An annular mandrel comprising a plurality of hollow members movablyconnected together and having perforated walls, one of said membershaving an air admission aperture and the connecting means between themembers comprising air conduit provisions.

12. A tube or air bag mandrel for pneumatictire manufacture comprising aplurality of hollow sections movably secured together end to end andhaving perforated sides.

13. A circular tube mandrel comprising a hollow body having perforatedsides and an inlet aperture for compressed air.

In testimony whereof, I hereunto affix my signature.

HARVEY F. MARANVILLE.

